Method and apparatus for implementing a high-reliability load balanced easily upgradeable packet technology

ABSTRACT

A network is defined with several alternative softswitches/proxies, which may be used for communication. Each softswitch/proxy has a unique Internet Protocol (IP) address. The softswitches/proxies receive configuration data from a centralized user-profile server, which maintains user-profile information. A centralized call-detail record (CDR) server is connected to each softswitch/proxy and maintains CDRs on each user on each softswitch/proxy. Based on the network configuration, an end-device configuration system generates a provisioning file. The provisioning file includes the IP addresses of each softswitch/proxy. The provisioning file is communicated to user devices. Each user device accesses the provisioning file and uses the IP address for communication. Should the communication fail for any reason, the user device may autonomously access the provisioning file and initiate another call using the next IP address in the provisioning file.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/116,108, filed May 6, 2008, which is currently allowed and is acontinuation of U.S. patent application Ser. No. 10/328,357 filed Dec.23, 2002, now U.S. Pat. No. 7,369,538, both of which are hereinincorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to communication networks. Specifically, thepresent invention relates to the architecture and operation ofcommunication networks.

2. Description of the Prior Art

Modern voice communication networks are implemented withcircuit-switched technology, packet-switched technology and wirelesstechnology. Circuit-switched technology is the more conventionaltelephone technology in which a single path (i.e., circuit) ismaintained between two communicating users. In packet-switchedtechnology, packets take different paths between two communicatingusers. In wireless technology, air is used as the communication medium.

While each of these technologies may be implemented separately, inmodern networks, these technologies are often integrated to enableend-to-end communications. For example, a user may use a conventionaltelephone connected to a circuit-switched technology to initiate atelephone call. The telephone call may initially traverse a conventionaltelephone network, such as the Public Switched Telephone Network (PSTN),and then crossover into a packet-switched network, such as an Internetprotocol based network (i.e., Voice-Over-IP). In addition, each of thesenetworks, the circuit-switched network and the packet-switched network,may provide the starting point for communication over a wirelessnetwork.

Circuit-switched networks have become a very stable technology. Thefoundational component of a circuit-switched network is the circuitswitch. In a conventional circuit-switched network, the circuit switchand processors within the circuit switch are designed to be highlyreliable. For example, software is written to manage failures in thecircuit switch or congestion in the network. In addition, if there is aproblem with the primary circuit switch, software techniques andprocedures are implemented to transition to a backup circuit switch.

However, providing a stable circuit-switched network is expensive andcomplicated. Since the circuit switch is “wired” to a customer, itpresents a single point of failure. In addition, the switch capacity istypically over engineered to avoid congestion, blocking orload-balancing problems in the network. Over engineering the networkadds to the cost of providing service. Furthermore, if there is adisaster at the location that houses the circuit switch, service isdisrupted and it is often very difficult to quickly restore service.Therefore, to provide a highly reliable solution, the locations thathouse these switches need to support backup power, diverse facilityroutes, etc. All of these issues add to the complexity and expense ofthe network.

In addition, maintenance of the circuit switch, such as softwareupgrades, has to be carefully implemented so that customers do notexperience a disruption of service. The maintenance process typicallyconsists of sequentially upgrading different parts of the network (i.e.,switch-by-switch or processor-by-processor upgrade). Therefore,maintenance is typically performed at night, which also adds to the costand complexity of operation.

As voice communications transition to packet networks, users willrequire the same reliability in packet networks as in thecircuit-switched networks. Initially, the same approach was taken inpacket-switched networks as in circuit-switched networks. Incrediblyrobust packet switches were implemented using robust processors so thatshould a failure occur, the failure could be managed. Many of theserobust features were implemented using very complex, proprietarysoftware algorithms and over-engineered hardware components.

As more commercial hardware and software became available, therobustness of the network was achieved by implementing redundantprocessors or redundant switches. For example, modern packet-switchednetworks are implemented using two softswitches (i.e., servers) eachconfigured in a similar manner. The servers exchange status messagesbetween each other. The status messages are referred to as a heartbeat.During configuration, one server is designated as the primary and asecond server is designated as the secondary (i.e., backup). As such,should the primary fail, communications can be transitioned over to thesecondary and the secondary would continue the communications. The twoservers/processors are given a single Internet protocol address.Therefore, to the rest of the network, the two servers appear as oneserver. Proprietary software then controls the identification of afailure and the transition of a call during the failure. The proprietarysoftware is located in each softswitch to detect the failure of themated pair (i.e., partner exchanging heartbeat) and then take over callprocessing, if necessary. The mated pair typically must reside in thesame physical location. In addition, power backup and a highly reliabledata network are required for interconnection. Thus, additional costsare required to provide a reliable environment/solution for a two-serverdesign implementing a heartbeat.

In addition to failures, maintenance needs to be carefully managed in atwo-server (i.e., two-processor) design implementing a heartbeat. Forexample, when performing maintenance, the two processors must besynchronized. As a result, complex algorithms need to be implemented tomake sure that the two processors are both upgraded in a synchronizedmanner. In addition, the maintenance or upgrades need to be performed sothat service to users is not disrupted.

There are a number of shortcomings with the two-server (i.e.,two-processor) design. For example, detecting a failure is oftenproblematic and since the transition to the second processor occurs whenthere is a failure of the first processor, the system may not transitionbecause of an inability to detect a failure of the first processor. Inaddition, there are a number of reasons why a processor may not respondto the heartbeat. For example, the processor may not receive theincoming call messages, the processor itself may fail, etc. Thus, it isoften difficult to identify and isolate the fault and, therefore,troubleshoot or initiate the transition to the second processor.

Once a problem is detected, the current calls need to be transitioned tothe second processor. Transition of the calls to the second processorrequires complex software algorithms so that the calls are not dropped.Typically, when there is a failure between two processors using theheartbeat, the call transition is accomplished by determining that thefirst processor is no longer available to handle the call.Communications then have to occur between the first and second processorto transition the call to the second processor. The call is thencontinued on the second processor. All of these steps need to occurduring the call. As a result, the process of transitioning andcontinuing a call is very difficult when using redundant processorscommunicating with a heartbeat.

Thus, there is a need for a method and apparatus that providesredundancy in packet networks. There is a need for a method andapparatus that performs load balancing in packet networks. There is aneed for implementing robust packet-switching networks that can easilyswitch calls, are easily upgradeable, and easily reconfigured.

SUMMARY OF THE INVENTION

The present invention increases the reliability of a voice network byintroducing a new network configuration and providing agent software toprovide intelligence in user devices. The present invention also reducesthe design and maintenance complexity of packet-telephone networks,thus, reducing equipment and operations costs.

In one embodiment of the present invention, a network comprises auser-profile server that stores user-profile information. Theuser-profile information may be any information that defines the user ortheir services. For example, the user-profile information may includeuser address information, contact information, etc. In addition, theuser-profile information may include information on the user callingplan, such as whether the user has call waiting, call forwarding, etc.

A network implementing the method and apparatus of the present inventionincludes a number of softswitches in communication with the user-profileserver. As such, the user-profile information is communicated from theuser-profile server to the softswitches in the network. In oneembodiment of the present invention, each softswitch includes the sameconfiguration information.

The softswitches in communication with the user-profile server include afirst softswitch including a first Internet Protocol (IP) address andstoring first configuration data in response to the user-profileinformation stored in the user-profile server. The first softswitch isthe primary softswitch. The first IP address is the IP address of thefirst softswitch. As such, communication with the first softswitch isaccomplished by directing packets to the first IP address. The firstconfiguration information defines the first softswitch as a recipient ofa user's communications and defines the services that the user mayaccess using the first softswitch.

The softswitches in communication with the user-profile server include asecond softswitch including a second IP address and storing the firstconfiguration information in response to the user-profile informationstored in the user-profile server. The second softswitch is a backupsoftswitch used in the event that the first softswitch is unavailablefor any reason. The second softswitch is designated with a second IPaddress, which is different from the first IP address. A user may sendcommunication directly to the second softswitch without any negotiationcorrespondence or dependence on the first softswitch. As a result, thefirst softswitch and the second softswitch each function independentlyof each other. Both the first softswitch and the second softswitch areconfigured in the same way. Therefore, the second softswitch stores thesame configuration information (i.e., first configuration information)as the first softswitch.

A call-detail server is in communication with the first softswitch andin communication with the second softswitch. The call-detail server isconfigured with call-detail information in response to the firstconfiguration information stored in the first softswitch and in responseto the first configuration information stored in the second softswitch.For example, the call-detail server is configured with a call-detailrecord for each user on each softswitch. Therefore, the call-detailserver may include a single call-detail record for each user or thecall-detail server may include an instantiation of a call-detail recordfor each time the user appears on a softswitch. For example, if thereare three servers, each configured to support a specific user (i.e.,primary softswitch, secondary softswitch, tertiary softswitch), thenthree call-detail records may be maintained for the user.

A configuration system is in communication with the first softswitch andin communication with the second softswitch. The configuration systemprovisions the network for the users by identifying which softswitch isthe primary softswitch, secondary softswitch, etc. The configurationsystem provisions the network by using a provisioning (i.e.,configuration) file including the first IP address, the second IPaddress, etc. The configuration system assesses the network anddetermines the paths, routes, etc. required to access the firstsoftswitch, second softswitch, etc. The IP addresses associated with thesoftswitches are then stored in a provisioning file and communicated toa user device.

A user device is in communication with the configuration system, thefirst softswitch and the second softswitch. The user device is anIP-ready device or a traditional telephone connected to an IP-readydevice. A provisioning file is communicated from the configurationsystem to each user device. The provisioning file includes a primary IPaddress and a secondary IP address. The user device makes a call to thefirst softswitch by using the primary IP address included in theprovisioning file. If the call is disrupted or does not get through forany reason, after a predefined time, the user device initiates a call tothe second softswitch. The user device may perform this process duringcall initiation or the user device may perform this process if the callis interrupted for any reason and the call needs to be transitioned tothe second softswitch.

In one embodiment of the present invention, a network comprises auser-profile server storing user-profile information; a first softswitchincluding a first IP address is in communication with the user-profileserver and stores first configuration data in response to theuser-profile information stored in the user-profile server; a secondsoftswitch including a second IP address is in communication with theuser-profile server and stores the first configuration data in responseto the user-profile information stored in the user-profile server; acall-detail server is in communication with the first softswitch and incommunication with the second softswitch, the call-detail server isconfigured with call-detail information in response to the firstconfiguration information stored in the first softswitch and in responseto the first configuration information stored in the second softswitch;and a configuration system is in communication with the first softswitchand in communication with the second softswitch, the configurationsystem provisioning the network and generating a provisioning fileincluding the first IP address and the second IP address. In addition,the network further comprises a user device in communication with theconfiguration system and capable of generating a call in response to thefirst IP address and in response to the second IP address included inthe provisioning file and generated by the configuration system.

A network comprises a user-profile server storing user-profileinformation; a plurality of softswitches, each including an IP addressassociated therewith and each in communication with the user-profileserver and storing configuration data in response to the user-profileinformation stored in the user-profile server; a call-detail server isin communication with each of the plurality of softswitches, thecall-detail server stores call-detail information in response to each ofthe plurality of softswitches; and a configuration system is incommunication with each of the plurality of softswitches, theconfiguration system provisioning the network by using a configurationfile including the IP address associated with each of the plurality ofsoftswitches. The network further comprises a user device incommunication with the configuration system and capable of generating acall in response to the IP address associated with each of the pluralityof softswitches included in the configuration file.

A user device comprises an interface receiving a configuration file, theconfiguration file including a first IP address and a second IP address;a first memory storing computer instructions; a second memory storingthe configuration file including the first IP address and the second IPaddress; and a processor coupled to the first memory and coupled to thesecond memory, the computer instructions causing the processor togenerate a call request to the first IP address and after a predefinedtime causing the processor to generate a call request to the second IPaddress.

A product comprises a computer usable medium storing computerinstructions and a configuration file including a first IP address and asecond IP address; the computer instructions causing the computer togenerate a first call connection in response to the first IP addressincluded in the configuration file; test the first call connection; andif the first call connection fails, generate a second call connection inresponse to the second IP address included in the configuration file andin response to testing the first call connection.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 displays a diagram of a network implementing the method andapparatus of the present invention.

FIG. 2 displays a flow diagram implementing a network method of thepresent invention.

FIG. 3 displays a flow diagram implementing a user device method of thepresent invention.

FIG. 4 displays a block diagram of a multi-function computerimplementing a method and apparatus of the present invention.

DESCRIPTION OF THE INVENTION

While the present invention is described herein with reference toillustrative embodiments for particular applications, it should beunderstood that the invention is not limited thereto. Those havingordinary skill in the art and access to the teachings provided hereinwill recognize additional modifications, applications, and embodimentswithin the scope thereof and additional fields in which the presentinvention would be of significant utility.

In one embodiment of the present invention, a softswitch or proxycommunicates with user devices, such as a Media Terminal Adaptor (MTA),IP phone, or Public Service Telephone Network (PSTN) gateway to providelocal dial tone and features, such as caller ID and call waiting forusers. For example, in one embodiment of the present invention, the PSTNgateway would be a user device and would be used for calls thatoriginate or terminate on the Public Switched Telephone Network (PSTN).

User-profile information is stored and maintained in a centralizeduser-profile server and dynamically downloaded to severalsoftswitches/proxies whenever the softswitches/proxies boot up or whenthe network configuration changes. Once the softswitches have beenconfigured, a provisioning file is constructed in an end-deviceconfiguration system. The end-device configuration system dynamicallyprovides the user devices with the IP addresses of a primary andalternate softswitch/proxy for communication.

The IP addresses are downloaded from the end-device configuration systemand stored in a provisioning file in the user device. Thesoftswitches/proxies send call event information to a centralized CallDetail Recording (CDR) system so that all of the users' calls can beproperly accounted for regardless of which softswitch/proxy handles thecall. The call-event information may include any information used forbilling, traffic engineering, or other administrative functions.

Using the IP addresses in the provisioning file, the user device has two(or more) softswitches/proxies that the user device can use forcommunication. As a result, if the primary softswitch is unavailable forany reason, the user device will use the IP address of the alternate(i.e., second) softswitch/proxy for communication. By storing and usingmultiple IP addresses, the user device is able to switch between theprimary and alternate softswitches/proxies.

During operation, when the user device attempts to make a call, if theprimary softswitch/proxy is unavailable, after a predefined time, theuser device will send call control signaling to the secondarysoftswitch/proxy (i.e., using the second IP address in the provisioningfile). Also, if the softswitch is in an overload condition, thesoftswitch can simply ignore new call requests, causing the IP phone torequest call setup using the secondary softswitch/proxy. As a result,load balancing is also achieved using the method and apparatus of thepresent invention.

In one embodiment of the present invention, load balancing may beimplemented by engineering the softswitch/proxy to ignore new callrequests when the system utilization reaches a threshold. For example,in the case of a two softswitch/proxy solution, if each softswitch/proxyis engineered to support 50% of the forecasted maximum load and theoverload threshold is set to 60% of maximum capacity (leaving a 10%buffer), then if one of the softswitches/proxies is at 60% of capacitysimply by ignoring new call requests, the new call requests will besupported by the other softswitch/proxy.

The method and apparatus of the present invention also simplifies themaintenance of the softswitch/proxy equipment. Since the user device isconfigured to “find” an available softswitch/proxy, maintenance staffcan simply take one of the softswitches/proxies out-of-service, performmaintenance, and then restore the softswitch/proxy back to servicewithout any interruption of service to the user device. If maintenanceis performed on the primary softswitch/proxy, the user device willaccess the secondary IP address and switch to the alternatesoftswitch/proxy. If the alternate softswitch/proxy is taken offline,the user device will continue communication with the primarysoftswitch/proxy.

FIG. 1 displays a communication network implementing the method andapparatus of the present invention. In FIG. 1, a number of user devicesare shown. A telephone is shown as 100. The telephone 100 is connectedto a Media Terminal Adaptor (MTA) 102. The MTA 102 converts analog-voicesignals coming from the telephone 100 into Internet packets forcommunications over the IP network 110.

The user device may be implemented as an Internet Protocol (IP)telephone 104. The IP telephone 104 may be any kind of Internet-readyappliance for receiving voice information and converting the voiceinformation into IP-compliant information, such as IP packets. Forexample, the IP telephone 104 may include a conventional telephone withInternet software and Internet-compliant interfaces. The IP telephone104 may include a Personal Data Assistant (PDA) capable of receivingvoice and communicating voice over the Internet (i.e., wireless orconnected PDA). Lastly, the IP telephone 104 may include amulti-function computer running telephone software and including aninterface connected to the IP network 110.

A telephone is shown as 106. The telephone 106 may connect to the IPnetwork 110 through a PSTN gateway 108. The PSTN gateway 108 may beconsidered a user device or the PSTN gateway 108 in combination with thetelephone 106 may be considered a user device. The telephone 106receives analog-voice information and communicates the analog-voiceinformation to the PSTN gateway 108 where the analog-voice informationis converted to IP-compliant communications for transmission over the IPnetwork 110. In one embodiment of the present invention, the PSTNgateway 108 may be implemented with a traditional circuit-switchedtechnology. In another embodiment of the present invention, the PSTNgateway 108 may be implemented with a packet-switched technology, suchas softswitch technology.

Various network components are connected to the IP network 110. Anend-device configuration system 112 is shown. The end-deviceconfiguration system 112 provisions Internet addresses and communicatesthose addresses to the MTA 102, the IP telephone 104, and the PSTNgateway 108. The end-device configuration system 112 may be implementedwith a multi-function computer or the end-device configuration system112 may be implemented with specialized hardware. In one embodiments ofthe present invention, the end-device configuration system 112 includesa plurality of Internet interfaces for receiving IP configurationinformation from softswitches in the network and communicatingprovisioning files to the MTA 102, the IP telephone 104, or the PSTNgateway 108.

In another embodiment of the present invention, the end-deviceconfiguration system 112 includes a database storing provisioninginformation. The provisioning information includes any informationrequired to perform provisioning in the network. For example, theprovisioning information may include the relationships between IPaddresses and softswitches. The provisioning information may correlateroutes, IP addresses, softswitches and users. The end-deviceconfiguration system 112 communicates the provisioning informationacross the IP network 110 to the MTA 102, the IP telephone 104, or thePSTN gateway 108. The provisioning information may be communicated as afile, which is used by the user devices to provision traffic across theIP network 110. As such, the configuration file including the IPaddresses may be considered a provisioning file.

The end-device configuration system 112 implements an algorithm, whichacquires (i.e., polls and receives or automatically receives) IPaddresses from various softswitches in the network. The algorithm maythen perform correlation and provisioning functions, such as designingrouting patterns etc. The end-device configuration system 112 thenprovides those IP addresses in the form of a provisioning file to userdevices within the network.

Several softswitches are shown. For example, a primary softswitch/proxyis shown as 116, an alternate softswitch/proxy is shown as 118, and analternate softswitch/proxy “N” is shown as 120. In one embodiment of thepresent invention, each softswitch/proxy is fully loaded and configuredwith information (i.e., configuration information, such as routing dataand algorithms) required to switch calls. Each softswitch/proxy may beimplemented with specialized hardware, software, or eachsoftswitch/proxy may be implemented in a multi-function computer underthe control of computer instructions, which direct the multi-functioncomputer to switch calls.

A centralized call-detailed record (CDR) server is shown as 114. Thecentralized CDR server 114 stores CDRs and records call activity foreach user on each softswitch/proxy in the network. For example, the CDRmay include any type of maintenance information including billing, usagestatistics, etc. The centralized CDR server 114 is configured such thatas calls are made from any softswitch/proxy in the network, the CDR inthe centralized CDR server 114 will be updated and maintained. Thecentralized CDR server 114 may be implemented with specialized hardwareor the centralized CDR server 114 may be implemented with amulti-function computer running under the control of computerinstructions. In addition, the CDRs may be stored in a database, such asa relational database, which is accessed by a processor in themulti-function computer.

A centralized user-profile server is shown as 122. The centralizeuser-profile server 122 is connected to each softswitch/proxy in thenetwork. The centralized user-profile server 122 maintains user-profileinformation. For example, the centralized user-profile server 122maintains information on the users' calling plan features, such as callwaiting, three-way calling, etc. The centralized user-profile server 122may be implemented in specialized hardware or may be implemented in amulti-function computer under the direction of computer instructions.The computer instructions direct the centralized user-profile server 122to communicate user-profile information to each softswitch/proxy in thenetwork.

A method of operating the network shown in FIG. 1 is disclosed by theflowchart shown in FIG. 2. The method of FIG. 2 will be discussed inconjunction with the network displayed in FIG. 1. The method ofoperating the network may be implemented in real-time, in non-real time,or at predefined times. At 200, new configuration is required. The newconfiguration may be required for a variety of reasons. For example,when a new telephone or user joins the network, new configurationinformation maybe required. When a user changes their profile orservices, new configuration information maybe required. Lastly, whenthere are any changes in the network, whether these are changes to thesoftswitches, changes to the end-device configuration system 112,changes to the centralized call-detail record (CDR) server 114, orchanges to the centralized user-profile server 122, new configurationmay be required.

When new configuration information is required, a number of differentcomponents in the network are updated. The components may be updatedsimultaneously, sequentially, or the components may be updated using analgorithm. The centralized user-profile data is updated as shown at 202.Each softswitch/proxy in the network is updated as shown at 203. Eachsoftswitch may be updated simultaneously, sequentially, or consistentwith an algorithm. Once each softswitch/proxy has been updated, theend-device configuration system 112 is updated as shown at 204 and thecentralized CDR server 114 is updated as shown at 206. The end-deviceconfiguration system 112 is updated with the IP address of allsoftswitches/proxies that are capable of switching calls. Thecentralized CDR server 114 is updated to include records for eachsoftswitch/proxy that is active in the network and capable of switchingcalls.

As shown at 208, a provisioning file (i.e., configuration file) isdownloaded from the end-device configuration system 112 of FIG. 1 acrossthe IP network 110 to a user device, such as the MTA 102, IP telephone104, or PSTN gateway 108. The provisioning file includes the IPaddresses of each softswitch/proxy in the network that may be used bythe MTA 102, IP telephone 104, and the PSTN gateway 108 to completecalls. For example, the provisioning file includes the IP address of theprimary softswitch/proxy 116 of FIG. 1, the alternate softswitch/proxy118 of FIG. 1, and the alternate softswitch/proxy “N” 120 of FIG. 1.Lastly, the CDRs stored in the centralized CDR server 114 of FIG. 1 areupdated so that maintenance and billing can be conducted as shown at214.

FIG. 3 displays a flowchart implementing a method of operating a userdevice. A user device, such as MTA 102 attached to telephone 100,receives a provisioning file with multiple IP addresses as shown at 300.The provisioning file is communicated from the end-device configurationsystem 112 of FIG. 1. The provisioning file includes several IPaddresses, one associated or correlated with each softswitch/proxy inthe network. For example, the provisioning file will include a primaryIP address for the primary softswitch/proxy 116, a secondary IP addressfor the alternate softswitch/proxy 118, and a number of other IPaddresses for alternate softswitch/proxy “N” represented by 120. Theprovisioning file includes all of these IP addresses and may be storedin the MTA 102, the IP telephone 104, or in the PSTN gateway 108.

When a user device, such as the telephone 100, IP telephone104,telephone 106, is ready to generate a call, a request is sent to thesoftswitch associated with the primary IP address as shown at 302. Therequest generates IP information, such as IP packets. The request is acall-signaling request to establish a call or continue a call on anothersoftswitch. The packets are communicated across the IP network 110 tothe primary softswitch/proxy 116. The user device, such as the MTA 102,IP telephone 104, or the PSTN gateway 108, will then wait for X numberof seconds for a response as shown at 304. If there is a response, thenthe call will continue using the primary softswitch associated with theprimary IP address as shown at 306.

If there is no response within X seconds, then the call request is sentout using an alternate IP address as shown at 308. This would requirethat the MTA 102, IP telephone 104, or the PSTN gateway 108 access thesecond IP address in the provisioning file and use the second IP addressto contact the softswitch associated with the second IP address. Forexample, the alternate softswitch/proxy 118 would be contacted using thealternate IP address.

The MTA 102, IP telephone 104, or the PSTN gateway 108 will then wait Yseconds to see if a response is received as shown at 310. If a responseis received or a call is connected in Y seconds, then call processing iscontinued with the alternate address as shown at 312. However, if thecall is not continued in Y seconds, an algorithm may process the call byusing each of the IP addresses in the provisioning file or an algorithmmay process a selected number of IP addresses in the provisioning fileto complete the call. In the alternative, if there is no response in Yseconds, a network announcement or a busy signal may be played a shownat 314 and the MTA 102, IP telephone 104, or the PSTN gateway 108 maywait Z seconds before initiating a call request using the primaryaddress as shown at 302.

Many of the components of the network displayed in FIG. 1 may beimplemented using a multi-function computer under the direction ofcomputer instructions, such as computer software. For example, thecentralized user-profile server 122 may be implemented with amulti-function computer. The primary softswitch/proxy 116, the alternatesoftswitch/proxy 118, and the alternate softswitch/proxy “N” 120 eachmay be implemented with a multi-function computer. The centralized CDRserver 114 may be implemented with a multi-function computer. Theend-device configuration system 112 may be implemented with amulti-function computer. The PSTN gateway 108 may be implemented with amulti-function computer. The MTA 102 may be implemented with amulti-function computer. The IP telephone 104 may be implemented with amulti-function computer.

FIG. 4 is a block diagram of a multi-function computer 400 implementingthe components of the present invention. In FIG. 4, a central processingunit (CPU) 402 functions as the brain of the multi-function computer400. Internal memory 404 is shown. The internal memory 404 includesshort-term memory 406 and long-term memory 408. The short-term memory406 may be Random Access Memory (RAM) or a memory cache used for staginginformation. The long-term memory 408 may be a Read Only Memory (ROM) oran alternative form of memory used for storing information. A bus system410 is used by the CPU 402 to control the access and retrieval ofinformation from short-term memory 406 and long-term memory 408. Inaddition, the bus system 410 may be connected to interfaces, whichcommunicate information out of the multi-function computer 400 orreceive information into the mutt-function computer 400.

In one embodiment, when a user device is implemented with amulti-function computer, computer instructions implementing the methodshown in FIG. 3 may be hard-coded and implemented in ROM 408. Inaddition, the provisioning file may be stored and accessed from RAM 406.In the alternative, both the computer instructions implementing themethod shown in FIG. 3 and the provisioning file may be stored in RAM406.

Input devices, such as tactile input device, joystick, keyboards,microphone, communications connections, or a mouse, are shown as 412.The input devices 412 interface with the system through an inputinterface 414. Output devices, such as a monitor, speakers,communications connections, etc., are shown as 416. The output devices416 communicate with the computer 400 through an output interface 418.

A user device, such as 102, 104 or 108 of FIG. 1, may be implementedusing the multi-function computer 400 of FIG. 4. In one embodiment ofthe present invention, an interface, such as the input interface 414,receives a provisioning file. The provisioning file includes a pluralityof IP addresses, each associated with a softswitch. For example, theprovisioning file may include a primary IP address and a secondary IPaddress. Computer instructions, which direct the user device, may bestored in a memory, such as ROM 408, RAM 406 or external memory 420. Thecomputer instructions may direct the user device to make a call. Theprovisioning file, which includes the addresses (i.e., primary IPaddress and the secondary IP address), may be communicated to the userdevice from an end-device configuration system and stored in RAM 406,ROM 408 or external memory 420. A processor, such as CPU 402, may accessthe computer instructions stored in RAM 406, ROM 408 or external memory420 and using the computer instructions generate a call request from theuser device (i.e., multi-function computer 400). In doing so, the CPU402 would access and use the primary IP address from the provisioningfile to complete a call through a primary softswitch. If the call is notsuccessful, after a predefined time, the CPU 402 may access and use thesecondary IP address from the provisioning file to generate a callrequest to the secondary softswitch. This process continues until a callis completed. In an alternative embodiment, this process may functionunder control of an algorithm which manages the process for using theprovisioning file. For example, every other IP address in a provisioningfile may be used or a second call may be made based on a timingalgorithm that includes an exponential component, etc.

The components of the method and apparatus of the present invention maybe implemented in a networked configuration. When implemented in anetworked configuration, the components of the present invention may beimplemented in a Local Area Network or across a distributed network. Forexample, the centralized user-profile server 122, the centralized CDRserver 114, and the end-device configuration system 112 may beimplemented in a networked architecture such as a client-serverarchitecture.

While the present invention is described herein with reference toillustrative embodiments for particular applications, it should beunderstood that the invention is not limited thereto. Those havingordinary skill in the art and access to the teachings provided hereinwill recognize additional modifications, applications, and embodimentswithin the scope thereof and additional fields in which the presentinvention would be of significant utility.

It is, therefore, intended by the appended claims to cover any and allsuch applications, modifications, and embodiments within the scope ofthe present invention.

What is claimed:
 1. A network comprising: a user profile server storinguser profile information; a first switch comprising a first internetprotocol address in communication with the user profile server andstoring first configuration data in response to the user profileinformation stored in the user profile server; a second switchcomprising a second Internet protocol address in communication with theuser profile server and storing the first configuration data in responseto the user profile information stored in the user profile server; and aconfiguration system in communication with the first switch and incommunication with the second switch, the configuration system for:generating a provisioning file including the first internet protocoladdress and the second internet protocol address, wherein the firstinternet protocol address is different from the second internet protocoladdress; and sending the provisioning file to a user device comprising atelephone, wherein the provisioning file instructs the user device toinitiate a first call to the first internet protocol address and whenthe call is not completed, to initiate a second call to the secondinternet protocol address.
 2. The network of claim 1, furthercomprising, the user device, wherein the user device is for receivingthe provisioning file generated by the configuration system, and whereinthe user device is for generating the first call in response to thefirst internet protocol address and the second call in response to thesecond internet protocol address included in the provisioning file. 3.The network of claim 1, wherein the first switch and the second switchare softswitches.
 4. The network of claim 2, wherein the user devicecomprises a telephony device.
 5. The network of claim 2, wherein theuser device is an internet protocol telephony device.
 6. The network ofclaim 2, wherein the user device is a media terminal adaptor.
 7. Thenetwork of claim 2, wherein the user device is a public servicetelephone network gateway.
 8. A method of operating a network,comprising: storing user profile information; storing firstconfiguration data in association with a first internet protocol addressin response to the user profile information; storing the firstconfiguration data in association with a second internet protocoladdress in response to the user profile information; generating aprovisioning file comprising the first internet protocol address and thesecond internet protocol address, wherein the first internet protocoladdress is different from the second internet protocol address; andsending, by a processor, the provisioning file to a user device, whereinthe user device comprises a telephone, wherein the provisioning fileinstructs the user device to initiate a first call to the first internetprotocol address and when the call is not completed, to initiate asecond call to the second internet protocol address.
 9. The method ofclaim 8, wherein the first configuration data is stored in a softswitch.10. The method of claim 8, wherein the first configuration data isstored in two distinct softswitches.
 11. The method of claim 8, whereinthe user device comprises a telephony device.
 12. The method of claim 8,wherein the user device is an internet protocol telephony device. 13.The method of claim 8, wherein the user device comprises a mediaterminal adaptor.
 14. The method of claim 8, wherein the user device isa public service telephone network gateway.
 15. A user devicecomprising: an interface for receiving a provisioning file, theprovisioning file comprising a first internet protocol address and asecond internet protocol address, wherein the provisioning file is forinstructing the user device to initiate a first call request to thefirst internet protocol address and when the call request is notcompleted, to initiate a second call request to the second internetprotocol address; a memory storing the provisioning file including thefirst internet protocol address and the second internet protocoladdress; and a processor using the provisioning file for generating thefirst call request to the first internet protocol address and after apredefined time causing the processor to generate the second callrequest to the second internet protocol address, wherein the firstinternet protocol address is different from the second internet protocoladdress.
 16. The user device of claim 15, wherein the user devicecomprises a telephony device.
 17. The user device of claim 15, whereinthe user device is an internet protocol telephony device.
 18. The userdevice of claim 15, wherein the user device comprises a media terminaladaptor.
 19. The user device of claim 15, wherein the user device is apublic service telephone network gateway.